1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
3 *
4 * Copyright 1997-2009 Sun Microsystems, Inc. All rights reserved.
5 *
6 * The contents of this file are subject to the terms of either the GNU
7 * General Public License Version 2 only ("GPL") or the Common Development
8 * and Distribution License("CDDL") (collectively, the "License"). You
9 * may not use this file except in compliance with the License. You can obtain
10 * a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
11 * or glassfish/bootstrap/legal/LICENSE.txt. See the License for the specific
12 * language governing permissions and limitations under the License.
13 *
14 * When distributing the software, include this License Header Notice in each
15 * file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
16 * Sun designates this particular file as subject to the "Classpath" exception
17 * as provided by Sun in the GPL Version 2 section of the License file that
18 * accompanied this code. If applicable, add the following below the License
19 * Header, with the fields enclosed by brackets [] replaced by your own
20 * identifying information: "Portions Copyrighted [year]
21 * [name of copyright owner]"
22 *
23 * Contributor(s):
24 *
25 * If you wish your version of this file to be governed by only the CDDL or
26 * only the GPL Version 2, indicate your decision by adding "[Contributor]
27 * elects to include this software in this distribution under the [CDDL or GPL
28 * Version 2] license." If you don't indicate a single choice of license, a
29 * recipient has the option to distribute your version of this file under
30 * either the CDDL, the GPL Version 2 or to extend the choice of license to
31 * its licensees as provided above. However, if you add GPL Version 2 code
32 * and therefore, elected the GPL Version 2 license, then the option applies
33 * only if the new code is made subject to such option by the copyright
34 * holder.
35 */
36
37 package javax.faces.component;
38
39 import javax.faces.context.FacesContext;
40 import java.util.List;
41 import java.util.ArrayList;
42 import java.lang.reflect.Array;
43
44 /**
45 * <p>
46 * Utility class to enable partial state saving of Lists of attached objects
47 * such as <code>FacesListener</code>s or <code>Validator</code>s.
48 * </p>
49 */
50 @SuppressWarnings({"unchecked"})
51 class AttachedObjectListHolder<T> implements PartialStateHolder {
52
53 private boolean initialState;
54 private List<T> attachedObjects = new ArrayList<T>(2);
55
56
57 // ------------------------------------- Methods from PartialStateHolder
58
59
60 public void markInitialState() {
61
62 if (!attachedObjects.isEmpty()) {
63 for (T t : attachedObjects) {
64 if (t instanceof PartialStateHolder) {
65 ((PartialStateHolder) t).markInitialState();
66 }
67 }
68 }
69 initialState = true;
70
71 }
72
73
74 public boolean initialStateMarked() {
75
76 return initialState;
77
78 }
79
80
81 public void clearInitialState() {
82
83 if (!attachedObjects.isEmpty()) {
84 for (T t : attachedObjects) {
85 if (t instanceof PartialStateHolder) {
86 ((PartialStateHolder) t).clearInitialState();
87 }
88 }
89 }
90 initialState = false;
91
92 }
93
94
95 // -------------------------------------------- Methods from StateHolder
96
97
98 public Object saveState(FacesContext context) {
99
100 if (context == null) {
101 throw new NullPointerException();
102 }
103 if (attachedObjects == null) {
104 return null;
105 }
106 if (initialState) {
107 Object[] attachedObjects = new Object[this.attachedObjects.size()];
108 boolean stateWritten = false;
109 for (int i = 0, len = attachedObjects.length; i < len; i++) {
110 T attachedObject = this.attachedObjects.get(i);
111 if (attachedObject instanceof StateHolder) {
112 StateHolder sh = (StateHolder) attachedObject;
113 if (!sh.isTransient()) {
114 attachedObjects[i] = sh.saveState(context);
115 }
116 if (attachedObjects[i] != null) {
117 stateWritten = true;
118 }
119 }
120 }
121 return ((stateWritten) ? attachedObjects : null);
122 } else {
123
124 Object[] attachedObjects = new Object[this.attachedObjects.size()];
125 for (int i = 0, len = attachedObjects.length; i < len; i++) {
126 attachedObjects[i] = UIComponentBase.saveAttachedState(context, this.attachedObjects.get(i));
127 }
128 return (attachedObjects);
129 }
130
131 }
132
133
134 public void restoreState(FacesContext context, Object state) {
135
136 if (context == null) {
137 throw new NullPointerException();
138 }
139 if (state == null) {
140 return;
141 }
142
143 Object[] attachedObjects = (Object[]) state;
144 if (attachedObjects.length > 0 && attachedObjects[0] instanceof StateHolderSaver) {
145 // overwrite the existing attachedObjects with those included
146 // in the full state.
147 if (this.attachedObjects != null) {
148 this.attachedObjects.clear();
149 } else {
150 this.attachedObjects = new ArrayList<T>(2);
151 }
152 for (int i = 0, len = attachedObjects.length; i < len; i++) {
153 T restored = (T) ((StateHolderSaver) attachedObjects[i]).restore(context);
154 if (restored != null) {
155 this.attachedObjects.add(restored);
156 }
157 }
158 } else {
159 // assume 1:1 relation between existing attachedObjects and state
160 for (int i = 0, len = attachedObjects.length; i < len; i++) {
161 T l = this.attachedObjects.get(i);
162 if (l instanceof StateHolder) {
163 ((StateHolder) l).restoreState(context, attachedObjects[i]);
164 }
165 }
166 }
167
168 }
169
170
171 public boolean isTransient() {
172
173 return false;
174
175 }
176
177
178 public void setTransient(boolean newTransientValue) {
179
180 // no-op
181
182 }
183
184
185 // ------------------------------------------------------ Public Methods
186
187
188 void add(T attachedObject) {
189
190 clearInitialState();
191 attachedObjects.add(attachedObject);
192
193 }
194
195 void remove(T attachedObject) {
196
197 clearInitialState();
198 attachedObjects.remove(attachedObject);
199
200 }
201
202 T[] asArray(Class<T> type) {
203
204 return new ArrayList<T>(attachedObjects).toArray((T[])Array.newInstance(type, attachedObjects.size()));
205
206 }
207
208 }